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Toxicological information

Acute Toxicity: oral

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Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
No data
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to an appropriate OECD test guideline, with acceptable restrictions. The restrictions were limited reporting of test substance information, and animal experimental conditions.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1982
Report date:
1982

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
GLP compliance:
not specified
Test type:
standard acute method
Limit test:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
Chlorotrimethylsilane
EC Number:
200-900-5
EC Name:
Chlorotrimethylsilane
Cas Number:
75-77-4
Molecular formula:
C3H9ClSi
IUPAC Name:
chloro(trimethyl)silane

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals or test system and environmental conditions:
Hilltop-Wistar albino rats weighed between 200 and 300 g.
TEST ANIMALS
- Source: No data
- Age at study initiation: No data
- Weight at study initiation: 200-300 g
- Fasting period before study: overnight
- Housing: No data
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: No data


ENVIRONMENTAL CONDITIONS
- Temperature (°C): No data
- Humidity (%): No data
- Air changes (per hr): No data
- Photoperiod (hrs dark / hrs light): No data


IN-LIFE DATES: No data

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
other: Silicone L-45 oil
Details on oral exposure:
Hilltop-Wistar albino rats received the test material neat or as a 25% dilution (v/v) in Silicone L-45 Oil by stomach intubation with a ball-end stainless steel needle.  
Doses:
Males: 8.0, 4.0, and 2.0 mL/kg; Females: 8.0, 5.7, and 4.0 mL/kg
No. of animals per sex per dose:
5/sex/dose
Control animals:
no
Details on study design:
Animal weights were recorded at 0 days (before dose), 7 days and 14 days (just prior to sacrifice).  At death or sacrifice, each animal was subjected to gross pathologic evaluation. 
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Weighing on Day 0 (before dosing), 7 days and 14 days (prior to sacrifice)
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, gross pathological evaluation
Statistics:
LD50 values were calculated by the moving average method (Thompson, 1947) and were based on a 14-day observation period.

Results and discussion

Effect levelsopen allclose all
Sex:
male
Dose descriptor:
LD50
Effect level:
< 0.25 mL/kg bw
Based on:
test mat.
Remarks on result:
other: Neat
Sex:
male
Dose descriptor:
LD50
Effect level:
5.66 mL/kg bw
Remarks on result:
other: 25% solution in silicone L-45 oil
Sex:
female
Dose descriptor:
LD50
Effect level:
6.63 mL/kg bw
Remarks on result:
other: 25% solution in silicone L-45 oil
Mortality:
All male animals died when administered with neat test substance. Females were notadministered the neat test material, based on effects on males.
Males: 5/5, 0/5, and 1/5 at 8.0, 4.0, and 2.0 mL/kg, respectively
Females: 5/5, 0/5, and 0/5 at 8.0, 5.7, and 4.0 mL/kg, respectively
Clinical signs:
MALES:
Dosage: 8.0 ml/kg
Signs of Toxicity: Sluggishness at 2 min; dyspnea and rales
in 2 at 2 min; prostration at 15 min; death of 4 at 30 to 45
min.
Dosage: 4.0 ml/kg
Signs of Toxicity: Fur yellow, ruffled, greasy in texture at
1 day. Normal appearance at 4 days.

Dosage: 2.0 ml/kg
Signs of Toxicity: None noted

FEMALE
Dosage: 8.0 ml/kg
Signs of Toxicity: Sluggishness, salivation, dyspnea, rales
at 2 min; prostration at 15 min; death of 4 at 30 min to 4
hr.

Dosage: 5.7 ml/kg
Signs of Toxicity: Slight sluggishness at 10 min. Recovery
at 1 day.

Dosage: 4.0 ml/kg
Signs of Toxicity: Fur yellow, ruffled, greasy in texture at
1 day. Normal appearance at 4 days.
Body weight:
MALES:
Dosage: 8.0 ml/kg
Weight Change (g): all died

Dosage: 4.0 ml/kg
Weight Change (g): 7 days = 55 to 77; 14 days = 83 to 131

Dosage: 2.0 ml/kg
Weight Change (g): 7 days = 72 to 90; 14 days = 115 to 124

FEMALE
Dosage: 8.0 ml/kg
Weight Change (g): all died

Dosage: 5.7 ml/kg
Weight Change (g): 7 days = 23 to 43; 14 days = 32 to 57

Dosage: 4.0 ml/kg
Weight Change (g): 7 days = 28 to 43; 14 days = 40 to 52
Gross pathology:
MALES:
Dosage: 8.0 ml/kg
Gross Pathology: Stomachs filled with black solid material, white vapor released when cut; livers blanched, tan; spleens enlarged.

Dosage: 4.0 ml/kg
Gross Pathology: Nothing remarkable

Dosage: 2.0 ml/kg
Gross Pathology: In victim, lungs dark red; red fluid in thoracic cavity; intestines red. In surivors, nothing remarkable.

FEMALE
Gross Pathology: Lungs of 1 red and black, vapor released when thoracic cavity cut; lungs of 1 with dark patches, red fluid in thoracic cavity; stomachs filled with black solid material, vapor released when cut; livers blanched, tan.

Dosage: 5.7 ml/kg
Gross Pathology: Nothing remarkable

Dosage: 4.0 ml/kg
Gross Pathology: Nothing remarkable

Applicant's summary and conclusion

Interpretation of results:
harmful
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
In a well-reported acute oral toxicity study conducted using a protocol similar to the now deleted OECD test guideline 401 (of unknown GLP status), the LD50 was 5.66 ml/kg (in a 25% (v/v) dilution in Silicone L-45 oil) for males, and 6.63 ml/kg (in a 25% (v/v) dilution in Silicone L-45 oil) for females. For neat test substance, the LD50 was <0.25 ml/kg, equivalent to <214 mg/kg for males.

Executive summary:

In a well-reported acute oral toxicity study conducted using a protocol similar to the now deleted OECD test guideline 401 (of unknown GLP status), male Wistar rats were dosed with 0.25 ml/kg undiluted Organochlorosilane A-161 by oral gavage. All of these animals died within six days and autopsy showed features consistent with severe irritant and ulcerogenic effects on the alimentary tract. These findings indicated a high degree of acute oral toxicity, and therefore the study was not conducted in females. A 25% dilution in Silicone L-45 oil was significantly less toxic, and LD50s for males and females were 5.66 and 6.63 ml/kg, respectively. Signs of toxicity included sluggishness, breathing difficulty and prostration. Gross pathology in the victoms revealed discoloured organs, fluid in the thoracic cavities and black solid in the stomachs.